Grinding machine



' 4 sheets-shee' l1 R. H. CRAMER GRINDNG MACHINE Original Filed Jul;r30,' 1940 oct. 9, 1945.

Oct. 9, 1945. R. H. CRAMER l GRINDING MACHINE 4 shets-sheet 2 OriginalFiled July 50, 1940 Oct. 9, 1.945. R. H'cRAMER GRINDING MACHINE original.Fild July 5o, 1940 4 Sheets-Sheet 3 346 STA/434 Oct. 9, 1945. R, H.CRAMER GRINDING MACHINE 4 Sheets-Sheet 4 Original Filed July 30, 1940`GAL/6F Immer/#6 MWL ela

Patented Oct. 9, 1945 te General Meters cerperatimpeaeitjMiehg acorporation of Delaware Original application Ju mary 1.6, 1943.

Divided andC this application- May 20, 1942, 'serial No. 443,756

16 Claims. ninvertion relates` A to gr -in dingV -machinesand"`qinprises alllof theieatures and aspects of nove yherein disc1psed.An object of the inveii "en -iste provide an improved Asizing mechaforcontrolling the machining of work pieces toman) predeltern-linedl size.Another object is to provide improved means for actuating and 'reset'ting the releasable sizing levers or electric contact "making members ofa sizing gauge.V Ane otherffcbject iste provideimproved means Aforactua/ting afeeler gauge as to control its engagement-, witn and separation from the Work.

' Ifo' 'these ends and dalso tcimprove generally-A upo sistm andclaimed, In itsgbroader aspects, the inven# 016e iene# znsesearilstilu'tion selected f rillustrative purposes in the accompanymg drawingsin which Fgf .1 iS from elevation@ the. machine.

2 isa sectional view of a detail. Fig 3 .iS a Side view, partly insection, ef che rockable gaugemounting and associatedparts.

lfig jl is an end view of some of the elements Offge.

1if.:." 5 'i s` chiefly a.

evicesfq-fthis enaractenthe invention cone n' ,thevariousmaitershereinafter described front elevation of gauging4aridsdoine' parts being broken awayand in dfllefwo ffiegauee box. isaverticalsectionloiFig. 6.

is an electrical and hydraulicdiagram 'IInsfepplQatiQnis adiyision of myapplica' tion Serial Number 3,518,398 which is noW Patent nihfsin moredetail.

I lhe'vvorl; surface to begaugedduring a ma'L chining operation such asgrinding is herein shovv'nmfor example as a tapered surface' 2 (Fig. 4)'on the inner race ring 6 for a tapered roller bearing which is clampedin a chuck C whose spindle; is journalied 1in a Work headjH and drivfnby a pulley 42 connected by a belt (not thro nvr/ hiena drive'fshafflsrertendsl Thev workspaces cricca; by e were sizing feeler orforli' 'gauge G during grinding andthe work piecfis v ejectedafter'grinding by an ejector yglimied to the specific cone es, the gauge boxcover kleinere- A 3 and wl i ich vshows co-operating mecha'- carrier 52?receiving the workv .piecesin 'successionyfrom a 'masazinegl the carrierheme; mounted on aslidelll] Whichfis reciprocated by a cylinder u riit544` all mounted on a bracket 94 whosebaseZ is `fastened to thehousinglllll.

When the work head H Yis adjusted (to their prcperxanglat racer/ay,surface is ground by a grindingfwheel W whichis fed normal to thesurface. by afieedslidelli guided by" doyetail; waysA ci avbase plate2,the Wheel spindle preierablyibeing given a, shoriileciprocatin; bygearine in; a caSng'$0I. Dur ing grinding; the feedUA Slidey isi fedbyra; .f eed. Screw ,whicncan be oper-v ateyimallually bya hand, Wheelldjhaving a handle 676 or by pawl and ratchet; mechanism which;

is actuated by cylinder and piston units. A paWl 70510113.11 arm 710which is pivoted to. apiston rod -l l 2 projecting from a cylinder 122has an adjustablethrow which is first -ample for coarsefeedjandthereafter more limited for ne feed. j W A `bar 'H6 clamped onthe piston rod carries two;

adjlltableflimit screws "124 and 126; the first adapted to engage a stoplug 121 on the cylinder duringcoarse feeding. The other screw '|26restricts the stroke of the piston rod Vfor ne feedingjwlien a swinginglatch lever 128'is swung t under it. The latch lever is a bell`crankfpivoted Qnthe v cylinder and'urged to inoperativeoutyvarqpositionbya coil spring 130. The lever is moved to operativeposition by a push solenoid 13f l which is actuatednnder control of theWork gauge which completes the solenoid circuit when the v vorkis nearlyd own to size, as will later appear. The ratchet mechanism is laterturned baclgwardlyor reset bya pawl 686 on an arm 690 actuatedgbyaretracting cylinder unit '160. The pawl 6&6 -normallyfengages'a stopscrew 152 adjustably mounted in aiixed lug 154.1

'I he Work contacting-[feder or forked gaugefG n is mounted forpivotalmovement (Figsy and 4) ing' spring which is seatedon a plate alcmade Aline vv il ;h ag1 upper bearingsleeve on ra conical seat aslidablev sleeve f cap 422. The centering spring lets the gauge feelerfloat and center itself by contact with the work, the pivot studs beingslidable axially in their bushings to a small extent.

The upper stud 418 is long enough to project through the upper bearingsleeve and has an arm 424 pinned thereto, the arm carrying a water seal426 covering the upper bearing sleeve. The arm 424 projects upwardly andcarries an adjusting screw 428 adapted to engage a hardened insert 438in a shiftable actuating rod 432 which slides in guide bushings 434. On`the top of the work head is a dovetail base plate 346 (Fig. 2)supporting a slide 348 having a standard 349 to which a bracket 356 isadjustably attached by bolts 368 passing through a slot 353. The bracketsupports dressing mechanism (not shown and of no immediate interest) butits suppcrtingbasev plate 346 is bored to receive and hold the abovementioned `guide bushings 434. The rod 432Y is urged in one direction byaicoiled spring 438 and its innerend carries a fork 440 looselyembracing a head 442 on a plunger projecting from a gauge support orindicator box 444 adjustably mounted by a-bracket 446on the work head. YAs will later appear', the spring yieldably causes resetting of certainmovable gauge contacts in :the indicator box when the work sizing feeleror fork gauge Gris moved out of engagement with the work, the springthen causing the fork 440 to pull the headed plunger outwardly to theright in Fig. 5. Hardened inserts are inserted between the head 442 andthe fork 448 to transmit movement in the opposite direction from the rod432 to the headed plunger during gauging.

The feeler G straddles the work and its two diamond feeler points arenormally urged substantially parallel to the work axis andsubstantiallyllengthwise of the tapered work surface 2 being 'ground inorder to promote sensitivity. The feeler is urged against the work by acoiled spring 448 interposed between a nut 458 and a slidalble flangedbushing 452 which bears against a bifurcated actuating arm 454 attachedto the pivoted gauge bar 486. The nut and the bushing are supported on athreaded stud 456 threaded in the end of a. piston rod 458 and formingan extension thereof. The stud has an abutment or head 468 normallyspaced from but adapted to engage the outer surface of thebifurcated-arm 454 when the piston rod is pulled into its cylinder 462.This movement retracts the feeler from the work and controls theresetting of the gauge parts in the indicator box. "/When new work isinserted in the chuck,i a needle valve indicated in the diagram causesthe piston rod 458 to delay the return of the feeler until the surfacehas been ground well down towards the desired size. Y

The headed plunger 442 slides in a boss 464 on the indicatorpbox and theend of it engages the actuating arm of a bell crank lever 466 pivoted ona pivot screw 488 and carrying a plate in the form of a cylinder418vwhich engages the stem 4'12 of a visual indicator 414. The bellcrank lever is urged in one'direction by a coil spring 416 to cause itsactuating arm to engage the inner end of theheaded plunger 442. A pairof releasable contact making yor sizing levers 418 are pivoted on aneccentric shaft 488 which is angularly adjusted bya knob 482 and clampedby a nut 484. Eachflever carries a contact screw 486 adapted to engage al contact screw 488 on the box to complete an electric circuit. VA coilspring 498 urges eachleverin a direction to engage its hardened .to beslightly shorter than the other.

insert 492 with the cylinder or arresting plate 418 and eventually tosnap the lever to circuit completing position under control of thecylinder or arresting plate 41'8 which moves very slowly upwardly as thework changes in size. One lever is arranged to snap past the cylinderbefore the other, the two levers each having a slit and a wedging screw494 so that one can be adjusted As will appear, the first circuit to becompleted energizes aisolenoid which reduces the feed of a grindingwheel ratchet mechanism from coarse to ne and the other energizes asolenoid to stop a pawl feeding motor.- When the work feeler or gauge Gis withdrawn from the work, the sizing levers 418 are reset by theheaded plunger 442 which is pivoted loosely byra pin to a resettinglever 496 having hooks 498 tol engage behind bent pins 588 on the sizinglevers.

Referring to Figs. 8 and 9 showing the electrical and hydraulic circuitsand assuming a work piece has been carried to the ,chuck by the loader,the cylinder unit 544 causes retreat of the loader and starts thegrinding cycle by closing a normally open switch 552. l This energizes acoil 198 thereby closing'a two-pole switch 889 which'causes a coil 882to reverse a main reversing valve 884 supplied with pressure fluid froma pump886. Pressure fluid is directed through a pipe 888 to a series ofcylinders. Cylinder 626 causes the grind-y ing Wheel to have apreliminary quick advance ready for the ratchet operated coarse feed.Cyl--4 inder 1131)Y moves the retracting ratchet pawl in the idledirection ready to cause feed retraction when grinding is done. Thegauge shifting cylinder462 shifts the feeler towards the work but thismovement is rendered slow by a needle or throttle valve 818 and a ballcheck valve 812 which communicate with vthe pressure line or pipe 888 sothat contact of thefeelerlwith the workis postponed until 'the workhasreceived consider-'- able grinding, thus IeSSening-wear. The ballcheck valveby-passes the fluid only whenfthe fluid afterwards exhaustsAto th'e'pipe 888. l

As the main wheel slide is thus rapidly shifted forwardly by thecylinder 626, a contact screw 658 closes a normally open switch 652thereby energizing acoil 814 which closes a normally open three-poleswitch 816 and starts a pawl actuating motor 818 having a cam 828 whichrepeatedly reciprocates the plunger of avalve B22 piped to a pilot valve824 which causes repeated reciprocaticn of the piston rod in the pawlfeeding cylinder '122. Thus the feed pawl first imparts coarse feedingstrokes as determined by the'stop screw 124 of Fig. `l.A As rgrindingproceeds, the feeler gaugecontrols the release of the iirst sizing leverin the indicator box and va'circut'i's completed,

by the corresponding contact screws 486P and 488 to thereby close anormally' open switch 826. This causes the solenoid 134 to be energizedto swing the latch lever 128 and reduce the stroke ofthe pawl.

As the workv reaches cuit and actuates a double acting switch 828 oneanerevel'seibenlein valvet' .Thus the' pipe-f v iinal'size, the feeler,vgaugefcontrols the completion of? the secondrgauge cirline8Mtmecomesiannexhaust ilineasoithat' cylinder f unit, Mitretractsrlthemaintwheelfslideewhile 2 cyl'- ind'eruniti 6%quicklyiretractsvthe;ffeeler fgau'ge: andsresetsi-the cmovahles-gaugefcontacts'e and :the 1 retractingi cylinderil Gili resets Cthe.ratchetfmechanism-readyy-forea new feeds: Atwabout the :esame time coil835 reverses.farifourewayzfvalveMailand;

the.k .chucking cylinder-f1 lioperates'toirelease `the Werlisa;

As the cylinderaunitzsthus:retracts .theiwheel','l

transmitting movement fr'omvthe' feelerif tqfthgsiz'i: ing-member. I Y-Inl` a `machine :of ithe vcharacter :indicated-fad work head; "atol1head,i.apower. fun-iti connected? to -a sourceoffiuid-'flpressureforbringing'the toolafi andftheiworkinto machiningfcontact'fa-workien gaging-:feeleig:y an actuating 1 armrforl moving tl1-4 feelergcialspring flo'r-:urgingfthe:fe'elergt'owardsthei" work;a'=pis'tony rod-'for- 'operatingithe armi, a cyl-i Al0 Linder.vhaving-piping 'connect-ionslltoi:thei same energizefausolenoids85El:andttherebyrreverse the. valve 844 so that the chuckingcylindercauses the y new-fapiece:A to Ibeiclampedg thef.` operation fof.the

chucking cylinder? then :closingathef switch"` I I toenergizerasolenoidef'iand reverse the valve: 848 7l toi retract Vthe r: loader.vwhich."'starts'the .-newfgrind-i on the machih'eitogrind aconicalshoulder'ontheworkyetheiwheerbeingadvancedrby.affeed: cylinder 26.0 and-ibeingffafterwards Adressedfunder control` of a,cylinderzdfandta valve'iif.v This dressing can A be :made ft'o14 occurat'everynycle` by. keeping closeda `switch? 85de Th'en Iasthe cylinder:Zllifvvhich is connected nto" the' main vvalve Srcauses a-.switch262`1't0-frcloseg.' -a coil s220feffects compensation: -for' wheel wearand dressingzwhilefafsolenoidL856ire--- verses a valve 858 to operatethe dressing cylinder 364.. Thelatter lrstLclosesf-aswtch 311 toenergize a coil 860 for cooling water and later closes a switch 311A toenergize a coil 852 to thereby make the valve 853 return the dresser.

I claim:

1. In a machine of the ,character indicated, a work head, a grindingwheel, the work head and the grinding wheel being mounted for relativemovement of approach, a work engaging ieeler, a spring urging the feelertowards the work, a piston and cylinder unit for rapidly moving thefeeler to retract the feeler from the work, a throttle valve for slowingthe movement of the piston in the other direction to postpone thecontact of the feeler with the work, and means for bringing the work andthe grinding wheel into contact prior to contact of the feeler with thework.

2. In a machine of the character indicated, a Work engaging feeler, anactuating arm for moving the feeler, a spring for urging the 'feelertowards the work, a piston rod having an abutment normally spaced fromthe arm, the piston rod supporting the spring at one side of the arm andsupporting the abutment on the other side, a cylinder for moving thepiston rod to carry the abutment against the arm to render the springineiective and retract the feeler from the work, a sizing member, andmeans for transmitting movement of the feeler to the sizing member todetermine the size of the work.

3. In a machine of the character indicated, a work engaging feeler, anactuating arm for moving the feeler, a spring for urging the feelertowards the work, a piston rod passing through the spring and extendingfrom one side of the arm to the other, the piston rod having a headnormally spaced from the arm on the side opposite to the spring, acylinder for moving the piston rod to bring the head into or out ofcontact with the arm, a sizing member, and means for source of fluidpressure as thatof'th'e'powernnitii andthrottling-means in one ofthe'connect-ionsi to the @cylinder toprevent contactfof t'h'efeele'rwithl' the: workfuntil the kpower runitl has dfirst "operatedandisubstantialvmachining-has occurredy 5. Inf a machinefof'l ithe"character )indicated'gY a i work .head `for support-ing a work piece; atool-'head -i having-a.maoliiningf` tool to engage-the wo'rk piece;'=aworkl contacting --feele'r toicontrollthe-siz of the -ivor-kgf means`forbringing-th'e-worki andthieffltool-into AkmachiningJv contact;andlvmechanism'efore moving the feeler towards theworkglacontr`olli-'n'g-x devicev for starting-1saidfmeans-and-fsaidtmechanismgand a retarding device-in saidf-mec'man'ismuntilthe work andthe tool-.have -beenin machin-l ing.contactfor a substantialpor-tionofthe `-:rna-'-- chiningcperiod;V

6.` In: amachinef-of-the characterindicated-a* workh'eadfor-supportinglaworkpiece, atoo'lfhe'ad having a machining-tool toengagethe-workpiece; means for -bringing the-tool fand'-the-work"-'into" machining I contact, a work# contactingl` feelrrto*controlthe sizefofithe-workl a piston-'rod having *connection-withtheffeeler-acylinder having pipi;

ing connections for fluid pressure, a piston in the cylinder andconnected to the piston rod, throttling means in one of the pipingconnections to postpone contact of the feeler with the work until thetool and the work have rst been brought into contact and substantialmachining has occurred, and means controlled by said feeler when thework reaches size for causing the cylinder to retract the feeler fromthe work.

'7. In a machine of the character indicated, a gauge support, a movablecontact making member movably mounted on the support, a plate forarresting and releasing the member, a lever movably supporting the plateand having an actuating arm, a plunger slidable in the gauge support andengaging the arm, a work engaging feeler, and means for transmittinggauging movement from the feeler to the plunger.

8. In a machine of the character indicated, va gauge support, a movablecontact making member movably mounted on the support, a plate forarresting and releasing the member, a plunger slidable in the gaugesupport for actuating the plate to release the contact making member, acoil spring for moving the plunger in one direction, and a work engagingfeeler for controlling movement of the plunger in the other direction.

9. In a machine of the character indicated, a gauge support, a movablecontact making member movably mounted on the support, a plate forarresting and releasing the member, a plunger slidable in the gaugesupport for actuating the plate to release the contact making member, aresetting member connected to the plunger and having means to move thecontact making member to arrested position, a work engaging feeler, andmeans for transmitting gauging movement from the feeler to the plunger.

10. In a machine of the character indicated, a

gauge support, a movable contact makingjmember movably mounted on thesupport, ,a plate for arrestingand releasing themember, a plungerslidable in the gauge support for vactuating :the plate to release thecontact making member, a removablyrmounted onthe support, a plate forarresting and releasing the member, a plunger ,slidable in the gaugesupport for actuating the plate to release the contact making member, awork Aengaging feeler, and a member for controlling transmission oflmovement from the feeler to the plungensaid last-mentioned parts havinga connection comprising a head on the one and an embracing fork on theother.

12. In a machine of the character indicated, a gauge support, a movablecontact making member movably mounted on the support, a plate forarresting and releasing the member, a plunger slidable in the gaugesupport for actuating the plate to release the contact making member, ashiftable member for operating the plunger, a Work engaging feeler fortransmitting gauging movement to the plunger, the plunger and theshiftable member having a connection comprising a head onrthe one and afork on the other.

13. In a machine of the character indicated, a gauge support, amovablecontact making member movably mounted on the support, a plate forarresting and releasing the member, a plunger slidablel in the gaugesupport for actuating the plate to release the contact making member,and a resetting member connected to the plunger and having means torestore the contact making member to arrested position.

14. `In a machine ofv the character indicated, a gauge support, amovable contact making member movably mounted on the support, a platefor arresting and releasing the member, a lever movably supporting theplate and having an actuating arm, a plunger engaging the arm, a slidingrodv connected to the plunger, a Work Aengaging feeler for sliding therod in one direction, and a resetting lever connected to the plunger andhaving means to move the contact making member to arrested position. f

15. In a machine of the character indicated, a

Work head, a gauge bar having a pivotal mounting, agfeeler gauge securedto the bar and adapted to rengage the work, an actuating arm secured tothe gauge bar, the pivotal mounting comprising axially movable Divotstuds on the gauge bar and a centering spring urging the studs axially.

16. In a machine of the character indicated, a Work head, a gauge bar, afeeler gauge secured to the bar and adapted to engage the Work,` anactuating arm secured to the bar, pivot studs projecting from the gaugebar, bearings slidably and rotatably receiving the studs, one of thestuds having a supporting ball at its end, and a spring exertingpressure on the ball.

RAYMOND H. CRAMER.

